How to claim back your lost super

And the largest amount yet to be claimed has a staggering balance of $2.2 million.

New figures from the 2017/18 financial year released by the Australian Taxation Office revealed there are 6.2 million accounts waiting to be reunited with owners.

The average balance is $2933.

People who have changed their jobs, moved house or forgotten to update their personal details are among those most likely to have retirement savings missing.

Australian Taxation Office figures revealed there are 6.2 million accounts waiting to be reunited with owners.

In NSW, $4.9 billion in super is sitting idle in more than 916,000 accounts.

The largest amount is $2.2 million in a Killara account.

In Victoria, $3.5 billion in super is sitting idle in more than 630,000 accounts.

The largest amount is $1.5 million in a Toorak account.

In Queensland, $3 billion in super is sitting idle in more than 706,000 accounts.

The largest amount is $1.1 million.

In South Australia, $870 million in super is sitting idle in more than 160,000 accounts.

The largest amount is $1.7 million in an Adelaide account.

In Tasmania, $218 million in super is sitting idle in more than 46,000 accounts.

The largest amount in an account has more than $1 million.

In the Northern Territory, $201 million in super is sitting idle in more than 48,000 accounts.

The largest amount in an account has more than $690,000.

Being reunited with back lost or unclaimed superannuation can have a significant difference to the amount of money you have in retirement.

The money waiting to be claimed is resting in lost or unclaimed super accounts.

A lost super account is held by super funds where the fund has lost contact with the member and has not received a contribution for 12 months or more.

A lost account becomes unclaimed and is sent to the ATO where the amount is less than $6,000.

Accounts also become unclaimed where individuals are eligible to withdraw but the super fund cannot contact them.

The ATO's assistant commissioner, Graham Whyte, said Australians should check online to see if they have some of their own money that can be put back in their hands.

"People have become disconnected and what we want to do is reconnect them," he said.

The ATO has released postcode data that will allow Australians to check how much lost or unclaimed super is waiting to be claimed where they live.

Mr Whyte said members are being contacted by the ATO to try and reunite them with their hard-earned savings.

This could be you in retirement if you get all your unclaimed super back.

"It's your money and you've worked hard to earn it, it's your retirement savings and you will need it one day," he said.

The Association of Superannuation Funds of Australia's chief executive officer, Dr Martin Fahy, said Australians should be trying to recoup their money because it's these accounts only earn minimal interest at 2 per cent per year.

"A person aged 30 with $5,500 in lost super held by the ATO, will end up with $14,600 extra in their super account in today's dollars at the time of retirement at age 67, if they transfer that balance to their active account," he said.